The U.S. government has allocated $350 million to help the country prepare for the H1N1 flu virus as well as the seasonal flu. U.S. officials say a vaccine for the H1N1 flu could be available by October before the flu season starts in the northern hemisphere.

The World Health Organization (WHO) estimates that more than 400 people have died from the H1N1 flu virus out of some 90,000 confirmed cases. In June the WHO declared this outbreak to be the first pandemic in more than 40 years. Recently, WHO Director General Margaret Chan predicted the worldwide spread of H1N1 or the swine flu is certain.

"Once a fully fit pandemic virus emerges, its further international spread is unstoppable," she said.

Currently, countries in the southern hemisphere are beginning their flu season. Chile, Argentina and Australia are seeing large numbers of cases. The U.S. government held a summit July 9 to prepare for the start of the flu season in the northern hemisphere.

Secretary of Health and Human Services Kathleen Sebelius said government agencies at every level are preparing a defense against the H1N1 flu as well as the seasonal flu.

"We do not know exactly how the virus will present during the fall flu season, but our surveillance efforts have led scientists to believe the impact of the virus could worsen this fall or earlier," she noted.

The H1N1 flu virus spread to the United States from Mexico in April and by the end of the school year in June, the virus had shut down more than 700 schools.

Officials at the summit stressed that schools need to find a way to educate children who cannot attend class and businesses must learn to cope with high numbers of absent workers.

The virus continues to spread in the U.S. even though the official flu season ended in March.

Secretary Sebelius said hospitals should also plan for an overload of patients during the flu season.

"The summit is not about raising alarms or stoking fears," she added. "It's about being prepared."

A big part of that preparation is the development of a vaccine.

Dr. Anthony Fauci heads research on infectious diseases at the National Institutes of Health.

"I can say with confidence that we will have a vaccine that we will be making a decision on in the fall," he said.

Dr. Fauci says no vaccine will be released to the public unless it is proven safe. Human testing could begin in August. Researchers then must determine how much vaccine to produce and how many doses people will need.

Officials emphasized there are limitations on what they can do, even with the best vaccine and anti-viral medicine. They repeatedly spoke about the public's responsibility.

SEBELIUS: "… Washing your hands, coughing into your sleeve."

FAUCI: "… Throw away tissues that you sneeze into."

And when you are sick, do not spread germs to others by going out in public.